Pelagic thresher sharks are globally listed as endangered and are vulnerable to overexploitation due to their life-history traits. They frequent at a seamount in the Visayan Sea to benefit from parasite-removal from cleaner wrasses. Stereo-cameras were deployed at the cleaning stations and sexes and pre-caudal lengths were extracted from the footage. Stage-based models were developed to analyse the population dynamics and finite growth rate from five different scenarios. Demographic stochasticity was applied to the models to account for uncertainties in the model parameters. A comparative risk analysis was applied for the different scenarios to explore the risks of population decline. The results show that the juvenile and adult stages represents the highest effect on the population’s growth rate. Only the scenario where no fishing pressure was applied shows a positive finite growth rate with an increasing population. The scenarios where fishing pressure is applied to both juveniles and adults shows the strongest population decline. As the cleaning stations functions as an important habitat for the population, legislative protection and fishing regulations of Kimud Shoal is recommended to ensure effective conservation. Non-invasive collection of life-history parameters such as stereo-cameras rather than fishery-dependent data provide opportunities for population studies on vulnerable populations.Pelagic thresher sharks are globally listed as endangered and are vulnerable to overexploitation due to their life-history traits. They frequent at a seamount in the Visayan Sea to benefit from parasite-removal from cleaner wrasses. Stereo-cameras were deployed at the cleaning stations and sexes and pre-caudal lengths were extracted from the footage. Stage-based models were developed to analyse the population dynamics and finite growth rate from five different scenarios. Demographic stochasticity was applied to the models to account for uncertainties in the model parameters. A comparative risk analysis was applied for the different scenarios to explore the risks of population decline. The results show that the juvenile and adult stages represents the highest effect on the population’s growth rate. Only the scenario where no fishing pressure was applied shows a positive finite growth rate with an increasing population. The scenarios where fishing pressure is applied to both juveniles and adults shows the strongest population decline. As the cleaning stations functions as an important habitat for the population, legislative protection and fishing regulations of Kimud Shoal is recommended to ensure effective conservation. Non-invasive collection of life-history parameters such as stereo-cameras rather than fishery-dependent data provide opportunities for population studies on vulnerable populations.
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